JP2013023375A - Method for discharging aqueous bulk - Google Patents

Abstract

PROBLEM TO BE SOLVED: To propose a method for effectively treating spring water and suspended spring water inevitably generated upon discharge of aqueous bulk.SOLUTION: A method for discharging an aqueous bulk includes: when the aqueous bulk such as ore and coal is discharged from a cargo ship using a bridge crane and a grab bucket of an unloader, if suspended spring water while powder is being suspended in the spring water is generated during discharge work, adding a moisture absorbent to the suspended spring water to thereby make the moisture absorbent absorb at least the spring water and then discharging the absorbent with the bulk.

Description

  The present invention eliminates unloading troubles caused by the occurrence of spring water when unloading ores and coals containing moisture are unloaded from these transport ships or barges using a bridge crane or unloader. The present invention relates to a method for unloading a water-containing rose.

  Most of roses such as ore and coal are imported from abroad, and most of them are transported by ship. In recent years, many of these roses, especially ores and coal, have a high moisture content, and the moisture (spring water) is separated from the roses during the transportation process and is accumulated at the bottom of the hold. As a result, in the middle or the latter half of the unloading process by the unloader, a dent is formed after grabbing with the grab bucket for unloading, and the suspended spring water in which the powder and spring water are turbid is generated and collected. In addition, there was a problem that it eventually became a slurry state and hindered unloading.

  In order to solve such a problem, the methods as disclosed in Patent Documents 1 and 2 are conventionally used, that is, when spring water is generated, the spring water is once pumped through a drainage facility (suction machine). After that, methods such as resuming unloading have been proposed.

JP 60-204526 A Japanese Utility Model Publication No. 50-13339

  However, in the pumping and draining methods proposed in Patent Documents 1 and 2, in order to pump the spring water, the ship is moved to a place having drainage (pumping) facilities each time, or drainage (pumping). There is a problem that it takes time because the equipment itself is moved and pumped from the hold. In particular, the spring water appears in the depression that is generated after grabbing by the grab bucket in the middle of unloading. There was a problem that the work efficiency was greatly reduced. In particular, in recent years, ore and coal have become inferior, for example, those with high moisture content, and such problems have become more apparent.

  Furthermore, the conventional techniques proposed in Patent Documents 1 and 2 assume that only spring water is pumped, but the hollow portion generated after grabbing with a grab bucket is separated from a rose having a large particle size. In many cases, powder with a small particle size flows in, and many of them are mud (slurry). In this case, it is difficult to pump with a conventional pump, which has been a decisive obstacle for unloading.

  Therefore, an object of the present invention is to propose an effective treatment method for spring water and suspended spring water that are inevitably generated when unloading hydrous roses.

  As a solution that can overcome the above-mentioned problems of the prior art and is effective in achieving the above-mentioned object, the present invention can be used to remove a wet bulk material such as ore or coal from a cargo ship, a bridge crane, When unloading using an unloader grab bucket, if suspended spring water with powder suspended in the spring water is generated during unloading, a water adsorbent is added to the suspended spring water. Thus, a method for unloading a wet rose is proposed, wherein at least spring water is adsorbed on the moisture adsorbent and then unloaded together with the rose.

For the unloading method according to the present invention,
(1) Use of a polymer water-absorbing agent as the moisture adsorbent,
(2) The water adsorbent is added in an amount equivalent to more than 0.5 to 3.3 mass% of the amount of suspended spring water,
(3) The moisture adsorbent is added in an amount equivalent to 1.0 to 2.0 mass% of the suspended spring water amount,
(4) Adding a polymer water-absorbing agent to the suspended spring generation position, adding roses from other parts, stirring, and then unloading.
(5) The mixing ratio indicating the weight ratio of the rose water weight and the polymer water-absorbing agent that has absorbed suspended spring water is set to 7 or more,
However, it is considered that a more preferable solution can be provided.

  By adopting the method of the present invention having the above-described configuration, even when suspended spring water is generated during unloading in a cargo ship hold, by adding a water adsorbent, at least the water is adsorbed to the water. The solid material (spring water, water adsorbent, powder) is unloaded together with other roses after being adsorbed (absorbed / retained) by the agent, so that only the suspended spring water is pumped. Need not be performed. Therefore, since the unloading operation can be performed continuously without causing the interruption of the unloading operation as in the conventional case, the unloading efficiency is remarkably improved.

It is explanatory drawing which shows a mode that the loose thing in a cargo ship is unloaded using the grab bucket of an unloader. It is a conceptual diagram explaining the effect | action when a water | moisture-content adsorption agent is added to suspension spring water. It is a basic diagram of an experimental container. It is explanatory drawing of the unloading method according to this invention method.

  Generally, unloading ore and coal (hereinafter also referred to as “ores”), which are stored in cargo hold (loading room) 1 of cargo ships, are unloaded using bridge cranes or unloader grab buckets. In doing so, as shown in FIG. 1, a puddle of spring water is generated in the lower layer portion of the ore deposit layer. When the unloading operation progresses and reaches the middle layer to the lower layer, a hollow 4 is formed in a part of the rose deposit layer after grabbing with a grab bucket, and the hollow 4 is separated from mainly gravel-like ores. It is known that suspended spring water in which powder is dispersed and suspended is accumulated.

  When the suspended spring water is generated in the bulk sediment layer in the hold, unloading proceeds and the slurry gradually becomes slurried, and unloading with the grab bucket 5 of the unloader becomes difficult. Even if the slurry is once grasped by the grab bucket 5, it will flow out at the hopper or belt conveyor portion (not shown) in the unloader machine. Unloader operation cannot be continued. In particular, the bottom of the hold 1 is often in such a state, and the unloading work must often be interrupted.

  Therefore, in the present invention, when the suspended spring water is generated, a predetermined amount of a water adsorbent such as a polymer water absorbent is added to the suspended spring water in the depression 4 to After adsorbing (spring water + powder) to the moisture adsorbent (water absorption and water retention), it was unloaded with roses to improve its efficiency. That is, according to the method of the present invention, the moisture adsorbent adsorbing the suspended spring water and the powder together with the roses 2 such as ores are unloaded at the same time.

  FIG. 2 shows a state in which the moisture adsorbent (A) is added to the suspended spring water Wm containing the powder P. As shown in FIG. 2 (b), the suspended spring water Wm is granulated in a swollen form confined in the crosslinked structure of the moisture adsorbent (A) together with the powder (P), as shown in FIG. 2 (b). Turn into.

  That is, the suspended spring water Wm is absorbed in the moisture adsorbent (A) to become a solidified state (swelled state), and can be easily grasped by the grab bucket 5. The water Wm itself can be unloaded with the roses 2.

  In a preferred embodiment of the present invention, a water adsorbent is added to the suspended spring water Wm, and a gravel-like rose material 2 in the vicinity of the depression 4 or other part is added using a grab bucket 5, and if possible, further Stirring (operation for repeating grabbing and grabbing with a grab bucket) is desirable in terms of promoting the solidification action and increasing the efficiency of unloading work.

  The water adsorbent used in the present invention has a high water absorption rate, high water absorption and high water retention, and once absorbed, the water hardly releases even when a certain pressure is applied from an external force, for example, A polymer water-absorbing agent such as polyacrylate (sodium, potassium) resin is suitable. This polymeric water-absorbing agent belongs to a substance that does not exhibit tackiness even when moisture is adsorbed in the molecular structure after moisture absorption. In this sense, inorganic silica gel, activated alumina, zeolite, etc. may be used together. More preferred. These are also used in the form of powder or granules.

Next, an experiment conducted for confirming the effect of the present invention will be described.
This experiment was performed using an iron container C shown in FIG. Brazilian Calajas iron ore with high moisture content is used as hydrous rose ore, and it is charged into the iron container C in a conical shape, deposited and added with water. Then, a dent was made using a scoop to generate a puddle (equivalent to a suspended spring), and granular (bead) polyacrylic sodium salt resin was added thereto as the polymer water-absorbing agent.

  The results of this experiment are shown in Table 1. According to this, it has been found that simply adding a polymer water-absorbing agent causes the polymer water-absorbing agent after addition and water absorption to become traps (lumps) and hinders handling. Furthermore, the polymer water-absorbing agent is a drug that swells by taking in water several hundred times or more of its own weight. For example, a polymer water-absorbing agent (water-absorbing polymer polymer) has a characteristic of swelling about 400 times in pure water. However, as in the present invention, it has been confirmed that it is a practical limit to consider about 200 times in suspended spring water in which powder and spring water are in a suspended state. In addition, when the swelling rate of the added polymer water-absorbing agent is small, the swollen body is likely to jump, so it is expected to scatter to the outside of the conveyor when transported by a belt conveyor or the like. It is preferable that

  The amount of the water adsorbent (water-absorbing polymer) added to the suspension spring is set to about 0.000 times in terms of the swelling rate. Add to more than 5 mass%. When the swelling ratio is 30 times or more, the amount of the moisture adsorbent added is within 3.3 mass%. Preferably, as shown in Table 1, if the swelling rate is within 100 times, the amount of water adsorbent added is 1.0 mass% or more, and if the swelling rate is within 50 times, the amount of water adsorbent added is 2.0 mass%. It can be said that the following is preferable.

  As described above, in this experiment, simply adding sodium polyacrylate resin granules to Carajas iron ore results in a lumpy shape (agglomerate), but it is weak as an adsorbing action of powdered suspension spring water. Therefore, it was found that some further processing was necessary. Therefore, in this experiment, a stirring operation was performed in which the water pool portion formed in the central depression 4 portion was stirred with a scoop. This stirring operation is a simulation of repeated operations of grabbing and dropping with a grab bucket in an actual machine.

  It was also found that adding a polymer water-absorbing agent to the suspended spring water and adding another rose carajas iron ore to the suspension further improves the effect of the addition.

  Actually, when unloading the Carajas iron ore in the state shown in FIG. 4 (a) from the transport ship, the polyacrylate resin granule, which is a polymer water-absorbing agent, is 1.0 to 2.0 mass relative to the suspended spring water volume. An amount corresponding to% was added. The amount of the polymer flocculant relative to the amount of the suspended spring water is estimated from the grab bucket capacity because the suspended spring water is generated in the depression after grabbing with the grab bucket. This was done by determining the amount. Similarly, the numerical value 7 indicated as the mixing ratio was also estimated from the grab bucket capacity.

Next, after adding a polymer water-absorbing agent to the suspended spring water generated in the depression generated in the ore deposit in the hold, the suspension around the suspended matter (carajas iron ore) around the suspended spring water. It was poured into spring water and stirred using a grab bucket. That is, after repeating the operations of grabbing roses (polymer flocculant) and dropping and releasing with the grab bucket 5, the unloading operation was repeated.
As a result, by adding a polymer water-absorbing agent to the suspended spring water and stirring, the action of entanglement of the powder and the spring water molecules in the suspended spring water with the polymer polymer was promoted, and unloading became easier. In addition, only by repeated grabbing and dropping and opening, the polymers may gather together to form a large lump. Because of the fear of falling from the suspension spring, the mixture of the roses around the suspension springs and the weight ratio of the polymer water-absorbing agent that absorbed the suspension springs to 7 or more, A swelling body (polymer water-absorbing agent) obtained by absorbing suspended spring water in the rose was further dispersed.

  In particular, a large amount of water has remained in the bottom of the ship in the past, but residual spring water has also been reduced by the above treatment. From the above results, in the conventional transport of Carajas iron ore, the amount of water in Carajas iron ore itself is high. Therefore, when unloading to land, there is a lot of spring water and the suspended spring water is removed (drained). However, when the above-described unloading method conforming to the present invention is adopted, when the efficiency when there is no spring water is assumed to be 100%, unloading by the conventional drainage method can only achieve an efficiency of 65%. Was able to achieve an efficiency of about 92%.

  The above-described technique for unloading roses according to the present invention can be applied to the unloading work of loose objects such as gravel, sand, and grains in addition to the exemplified hydrous ore and coal.

1 Funakura 2 Roses 3 Spring 4 Depression 5 Grab Bucket A Moisture Absorbent C Iron Container P Powder Wm Suspension Spring

Claims (6)

  When unloading hydrous bulk material such as ore and coal from a cargo ship using a bridge crane or unloader grab bucket, suspended spring water with powder suspended in the spring water is generated during the unloading operation. A method for unloading hydrous roses, comprising adding a water adsorbent to the suspended spring water so that at least the spring water is adsorbed to the water adsorbent and then unloading with the rose.   2. The method for unloading a hydrous rose according to claim 1, wherein a polymer water-absorbing agent is used as the moisture adsorbent.   The method for unloading a wet rose according to claim 1 or 2, wherein the water adsorbent is added in an amount equivalent to more than 0.5 to 3.3 mass% of the amount of suspended spring water.   The method for unloading a water-containing rose according to any one of claims 1 to 3, wherein the moisture adsorbent is added in an amount equivalent to 1.0 to 2.0 mass% of the amount of suspended spring water.   The water-containing composition according to any one of claims 1 to 4, wherein a polymer water-absorbing agent is added to the suspended spring generation position, and the bulk material of other parts is added and stirred before being unloaded. How to unload roses.   6. The method for unloading hydrous roses according to any one of claims 1 to 5, wherein a mixing ratio indicating a weight ratio of a rose water weight and a polymer water-absorbing agent that has absorbed suspended spring water is 7 or more. .

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